I think 10 million is out of reach. For OoT (11 million cume) you have N64+3DS. If we say Wii U = N64 in the OoT scenario then Wii U is significantly weaker then N64 and likely would be fortunate to contribute half of what N64 contributed to OoT. So that puts a big burden on the shoulders of NX. If NX is a replacement for both Wii U and 3DS then you have the handheld market that can help oout. But it's anyone's guess as to whether the handheld market has reached its new, lower level, or whether it will weaken further due to phone/tablet gaming. If NX is basically a Wii U replacement with interoperability with handheld hardware then since there will be a significant cross over between Wii U users and NX users that means NX will be relying on a lot of people who played it on Wii U to buy it again for NX. That number wont be all that high.
I think 5million+ is a good and realistic ambition. Much more than that is bonus, and requires NX to go off like Wii/DS.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
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